This application claims the benefit of prior filed co-pending U.S. provisional application Ser. No. 60/341,700 filed Dec. 17, 2001 entitled “SUPPORT SYSTEM INTERFACE PARTS FOR SCREED SKI” by Paul M. Semler.
The present invention relates generally to screed ski support systems, and more specifically it relates to an improved screed ski support system that increases the accuracy, speed, and economy of screeding aggregate materials. The invention also relates to an improved screed ski support system that is capable of screeding multiple aggregate layers, one over the other. The invention also relates to an improved ski screed support system that is capable of conveniently screeding aggregate layers having arcuate edge boundaries. The invention also relates to an improved screed ski support system that is capable of screeding aggregate layers over existing solid surfaces, including surfaces of cured aggregates. The invention also relates to an improved screed ski support system that is capable of screeding aggregates at steep angles, including 90 degree angles or vertical surfaces.
Quite a variety of other screed ski support systems are known. For example, sometimes “2×4” boards are simply nailed to concrete form stakes. Sometimes wooden stakes are driven into the ground and used to support “2×4”s or metal pipes used as screed skis. Both approaches are inefficient, costly, and time-consuming. Wooden screed skis often are not straight, and often have rough, abrasive surfaces that cause undesirable resistance to moving the screed bar during the screeding operation. Wooden stakes are difficult to drive into the ground and split easily, causing further difficulty. Such wooden components are bulky, and become unusable rather quickly. Sometimes screed ski support systems are comprised of cast or machined “J” hooks mounted via an integral screw clamp to a steel stake which supports a 2×4 screed support (ski) parallel to and normally above the (concrete/sand/or other aggregate material) surface to be screeded. These screed ski support systems also are time-consuming and costly to use, and also are bulky. Quite a variety of other ski support systems also are known, as indicated in U.S. Pat. Nos. 5,173,004, 4,913,582, 2,551,826, 2,331,949, 2,306,671, 2,319,526, 5,212,919, 6,123,745 and 1,988,746.
Perhaps the closest known prior art is shown in U.S. Pat. No. 5,173,004, which discloses a system that provides Y-shaped reusable yokes having stems which are inserted into vertical pipe stakes that have previously been pounded into the ground to a certain level by means of a pounding tool that matches the upper ends of the stakes. A nail extending through a hole in the pounding tool serves as an indicator pin that can be aligned with a horizontal string line. The horizontal pipes are rested in the yokes to serve as screed skis. After the screeding operation, both the reusable yokes and the screed ski pipes are removed.
However, U.S. Pat. No. 5,173,004 has a number of shortcomings. The screed skis and support yokes cannot be retrieved without walking through and/or disturbing the screeded aggregate. The aggregate material disposed at a steep grade cannot be screeded using the system of U.S. Pat. No. 5,173,004 because the screed skis are not anchored to the support yokes and will slide or fall away from them. The aggregate material being screeded may cause a screed skis to be lifted from or “float” above the support yokes on the aggregate material, preventing accurate screeding. If the stakes are not pounded into the ground at a nearly perfect 90 degree angle relative to the longitudinal axis of the screed skis to be placed thereon, the screed ski elevation is not accurate. The system of U.S. Pat. No. 5,173,004 does not have any features which allow for fine adjustment of the support yokes on stakes that have been overdriven into the ground or other surface material which supports the aggregate material to be screeded.
All of the above described prior art screed ski support systems require that the user walk through the screeded material in order to retrieve the screed skis and the stakes or other supports for the screed skis. This, of course, disturbs the finish of the screeded material.
Thus, there remains an unmet need for an improved screed ski system that permits screeding operations to be accomplished more accurately, more rapidly, and more economically than has been achievable by the prior art.
There also remains an unmet need for an improved screed ski system that permits accurate, rapid, and economical screeding of multiple aggregate layers, one over the other.
There also remains an unmet need for an improved screed ski system that permits convenient screeding of aggregate layers having arcuate edge boundaries.
There also remains an unmet need for an improved screed ski system that does not require the user to walk through the screeded material in order to retrieve the screed skis and the stakes or other supports for the screed skis.
There also remains an unmet need for an improved screed ski system that facilitates convenient reusability of the screed skis and screed ski supports.
There also remains an unmet need for an improved screed ski system that is usable for screeding aggregate material on steep slopes.
There also remains an unmet need for an improved screed ski system that can be used to screed multiple layers of aggregate material, one on top of the other, using the same stakes and screed ski and ski support assemblies.